From a9d554a4ac91760a8236708fc33bcf0f7541af27 Mon Sep 17 00:00:00 2001
From: Davis King <davis@dlib.net>
Date: Wed, 5 Aug 2020 08:13:58 -0400
Subject: [PATCH] minor cleanup

---
 dlib/image_loader/png_loader.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/dlib/image_loader/png_loader.cpp b/dlib/image_loader/png_loader.cpp
index 490318d42..b85120f10 100644
--- a/dlib/image_loader/png_loader.cpp
+++ b/dlib/image_loader/png_loader.cpp
@@ -46,6 +46,10 @@ namespace dlib
         {
         }
 
+        // no copying this object.
+        FileInfo(const FileInfo&) = delete;
+        FileInfo& operator=(const FileInfo&) = delete;
+
         ~FileInfo()
         {
             if ( fp_ != nullptr ) fclose( fp_ );
@@ -174,7 +178,7 @@ namespace dlib
 
     void png_loader::read_image( std::unique_ptr<FileInfo> file_info )
     {
-        if ( !file_info ) throw image_load_error(std::string("png_loader: invalid file_info, it is NULL"));
+        DLIB_CASSERT(file_info);
 
         ld_.reset(new LibpngData);